title: Mechanical phenotype is important for stromal aromatase expression.
abstract: Evidence that aromatase expression in tumor-associated breast stroma is elevated, provides a rationale for use of aromatase inhibitors (AIs) in breast cancer treatment. However, regulation of local aromatase expression in cancer-free breast stroma is poorly understood. Recent clinical work indicates that stromal cells in dense breast tissue tend to express higher levels of aromatase than their counterpart from non-dense tissue. Consistent with the clinical observation, our cell culture-based study indicated that cell density, cell shape, and extracellular matrix (ECM) significantly induced stromal aromatase expression via a distinct signal transduction pathway. In addition, we identified a number of cell surface markers that are commonly associated with aromatase-expressing stromal cells. As mammographic density is one of the strongest and most prevalent risk factors for breast cancer, these findings provide a potential mechanistic link between alterations in tissue composition of dense breast tissue and increased stromal aromatase expression. Further exploration of the in vitro model system may advance understanding of an important problem in breast cancer biology.
authors.affiliation: Department of Molecular Medicine, Institute of Biotechnology, University of Texas, San Antonio, TX 78245, USA.
authors.forename: Sagar
authors.initials: S
authors.lastname: Ghosh
authors.forename: Tao
authors.initials: T
authors.lastname: Kang
authors.forename: Howard
authors.initials: H
authors.lastname: Wang
authors.forename: Yanfen
authors.initials: Y
authors.lastname: Hu
authors.forename: Rong
authors.initials: R
authors.lastname: Li
mesh_terms: D001141:Aromatase / Q000096:biosynthesis* / Q000235:genetics; D001940:Breast / Q000201:enzymology* / Q000473:pathology*; D001943:Breast Neoplasms / Q000201:enzymology* / Q000473:pathology*; D002452:Cell Count; D048430:Cell Shape; D005109:Extracellular Matrix / Q000235:genetics / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D006801:Humans; D008327:Mammography; D008565:Membrane Proteins / Q000235:genetics; D010641:Phenotype; D034741:RNA, Small Interfering / Q000235:genetics; D015398:Signal Transduction; D017154:Stromal Cells / Q000201:enzymology / Q000473:pathology
chemical_list: D008565:Membrane Proteins; D034741:RNA, Small Interfering; D001141:Aromatase